Shortly after entering office, President Trump asked his staff for a “comprehensive strategy” to defeat ISIS within 30 days. After all, this was one of his campaign promises—to do what the Obama administration had left undone. As this deadline approaches, we should ask ourselves what would actually be required to destroy ISIS.

The reality is, it would most likely necessitate a holistic and long-term approach in Iraq along the lines of George W. Bush’s 2007 surge. But this would cost the president significant political capital, especially with a public that has little taste for overseas adventures. Trump, despite his bluster, is unlikely to do this, which is why his “comprehensive strategy” on ISIS could be a non-starter.

A Power-Monger Exploits Grievances

The challenges in defeating ISIS are intimately linked with Iraq’s Sunni-Shia sectarian conflict. Much of the Islamic State’s rapid success in Iraq was due to the Sunni population’s marginalization and mistreatment by the hands of the Shiite-majority government, which ISIS exploited.

A quick refresher for those who need it: Iraq has three primary ethno-sectarian groups, the Sunnis, the Shiites, and the Kurds. The Kurds have an autonomous region in the north of Iraq where they are mostly left alone. The Sunnis, a minority in Iraq, were in control of the country under Saddam Hussein’s rule. When he was ousted following the U.S. invasion in 2003, the Shiite majority took control and sectarian violence broke out.

The Sunnis feared reprisals once they were out of power, and they were right to. They had suddenly become a vulnerable minority in the midst of a burgeoning sectarian war. When the 2005 Iraq elections came around, they boycotted, feeling that it was rigged against them. This was a manifestation of America’s failure to sufficiently engage the Sunnis and reassure them their rights as minorities would be protected under democratic rule.

The result was a sectarian conflict that raged into a civil war. The Sunnis allied with al-Qaeda fighters in an insurgency that bitterly battled Shiite as well as U.S. forces.

The Surge Temporarily Changed That

Then, in 2007, came the surge. This cohesive and comprehensive strategy employed a multi-faceted approach to defeating the insurgency that included diverse military and intelligence tactics. But it wasn’t just about more troops on the ground. Its success was rooted in its commitment to a holistic strategy that included reaching out to the Sunni minority and drawing them into the political process.

As the surge began to gain momentum, many Sunni tribes decided to ally with the United States against al-Qaeda, in what was called the “Anbar Awakening.” This alliance was crucial to crushing al-Qaeda’s power and influence in Iraq. The Sunni population began to trust the United States and believe they would be included in the political process moving forward.

When Iraq’s next parliamentary elections came around in 2010, the Sunnis participated. It seemed like the path to sectarian participation in the political process was possible. But when a moderate coalition was elected, the Obama administration failed to support it. Instead, they threw their weight behind the incumbent Shiite prime minister, Nouri al-Maliki, who was also supported by the Iranian Quds force.

Maliki remained in power and continued to ostracize the Sunni population with political purges, pushing them back toward the periphery. The Sunnis once again lost confidence in a political system. Then came ISIS.

When the Islamic State began to emerge in 2014, the group promised the Sunnis a seat at the table in exchange for their support. Clearly, ISIS has since taken advantage of this relationship and has turned many Iraqi Sunnis against the self-proclaimed caliphate. But the Sunnis are still unsure where they fit into the national political scene. Although Haider al-Abadi’s appointment as prime minister in 2014 has gone some way toward helping things, his pivot toward Iran and Iranian-backed Shiite militias in the fight against ISIS has made many Sunnis nervous.

Obama’s Next Mistake

The comprehensive approach of the surge only works with a president who is willing to go all in. This strategy worked under the Bush administration, because Bush was willing to use all of his political capital in the last two years of his presidency to fully implement it. It failed under Obama, because he was not.

After U.S. troops withdrew from Iraq in 2011, the Obama administration fought terrorists in Iraq, including ISIS, with only one element of the comprehensive strategy proposed during the surge—drone strikes. This followed directly from Obama’s campaign promise of getting American troops out of Iraq, no matter the cost. He did not want to be a wartime president.

This strategy was always doomed. You can’t fight a group like ISIS and win over the disenfranchised Sunnis from a bunker in the Nevada desert. It requires a holistic approach, including outreach—which means boots—on the ground.

But Obama wanted to use what sway he had in pushing through the Iranian nuclear deal. This, not the stabilization of Iraq, was going to be his signature foreign policy accomplishment, whose purpose was two-fold.

First, it would be certifiable proof that he was a skilled diplomat and an anti-war president, despite an ongoing war in Afghanistan. Second, and more to the point, it would pave a way for America to step back from the region, handing over the reins of regional hegemon to Iran. Obama wanted nothing more than to wash his and America’s hands of the Middle East.

Why Trump Won’t Do It

Trump is unlikely to devote the necessary political and military resources to stabilizing Iraq and defeating ISIS. Despite Trump’s promises to eliminate ISIS, he has made it clear that, like Obama, he doesn’t think America should have much of a presence in the Middle East. We should instead be focused on problems at home and let someone else, like Russia or Iran, step in. This is, primarily, what won him the election—his “America first” policy that puts Americans and American jobs at the top of the list. Trump will need to put whatever political capital he has toward this goal.

Few want to see our resources going toward another country’s problems.

When Trump said he would destroy ISIS, his supporters generally liked it. It made America sound strong. But ultimately it’s not what the working-class voters in the Rust Belt care about. They care about infrastructure, jobs, the economy, and getting a fair shake. They don’t care much about the Sunnis.

Most people, whether they voted for Trump or not, have no idea what would be involved in truly defeating ISIS. If they were told today that ISIS could be defeated, but that it would require billions of dollars and most of the administration’s attention for the next four years, few would support it.

This attitude is consistent with the last several years, which have seen rock-bottom levels of public support for engaging in foreign conflicts. Even during the worst moments of the Syrian civil war, when President Assad was using chemical weapons on his own people or bombing hospitals, there was little support for American intervention. Simply put, no one wants to hear about American soldiers dying overseas, no matter what it’s for. And few want to see our resources going toward another country’s problems.

While the Cat’s Away, the Mice Will Play

But as long as Iraq’s Sunnis are treated like second-class citizens and kept out of the political process, they will be susceptible to alternative powers in the country, like ISIS. In the absence of U.S. investment in Iraq, Iranian influence will only inflame sectarian tensions.

To convince the Iraqi government that it’s in its best interest to engage the Sunnis, perhaps by giving them regional autonomy like the Kurds, we would need to invest time and resources there. But this can’t be done without spending significant political capital in the region, something the Trump administration, with its ambitious goal to make America great again, seems unlikely to do.